Management of intracardiac thrombosis in newborns: a case series and a narrative review of the literature

Domenico Umberto De Rose^1,2*Federico Mecarini³Cosimo Marco Campanale¹Flaminia Pugnaloni²Chiara Passarella²Aurelio Secinaro¹Giorgio Bracaglia⁴Matteo Luciani¹Alessandra Toscano⁴Irma Capolupo²ANDREA DOTTA²

• ¹Bambino Gesù Children's Hospital (IRCCS), Rome, Italy
• ²Neonatal Intensive Care Unit, “Bambino Gesù” Children’s Hospital IRCCS, Rome, Italy
• ³Santa Rosa Hospital, Local Health Authority of Viterbo (ASL Viterbo), Viterbo, Viterbo, Italy
• ⁴Santa Rosa Hospital, Local Health Authority of Viterbo (ASL Viterbo), Viterbo, Italy

Background: Neonatal intracardiac thrombosis (ICT) is an uncommon but increasingly recognized condition that impacts neonatal morbidity and mortality, especially in critically ill term and preterm infants. Management includes supportive care and pharmacological or surgical intervention. This study explores the challenges associated with ICT in neonates.We described the clinical presentation and multidisciplinary management of two cases of intracardiac thrombosis. We also reviewed literature from Medline and PubMed using MeSH terms ("intracardiac thrombosis" AND "newborn").Case series: In the first case, a very early (day 1) atrial thrombosis was unusually attached at the fossa ovalis and floating between the right and left atrium in an early-term newborn with meconiumaspiration syndrome and fetal inflammatory response syndrome. In the second case, a late-preterm neonate developed a left atrial thrombus after resuscitation at birth, with severe anemia (hemoglobin 5 g/dL) requiring two blood transfusions. In both cases, treatment with low-molecular-weight heparin resolved the thrombus without complications.Results: Critically ill term and preterm neonates should be carefully monitored due to the increased risk of thromboembolic events. The timing and decision to treat ICTs remain challenging. Supportive therapy is always indicated, including treatment of conditions such as sepsis, dehydration, anemia, and coagulopathy. Anticoagulant therapy with low-molecular-weight heparin (LMWH) offers a favorable risk/benefit ratio, except in neonates at high hemorrhagic risk.Neonatal intracardiac thrombosis, though rare, requires high clinical suspicion and prompt multidisciplinary management. Early diagnosis and individualized anticoagulant therapy can lead to favorable outcomes while minimizing complications.